Name: Nikk
Comments: I have this rash under both armpits and I went to the dermatologist and he said I wasn't allergic to my deodorant or my detergent I have no idea what caused this. Any Ideas? And Its not a heat rash because I live up north.
You may not be allergic to your deodorant or the detergent used for washing but what of the unique combo they will produce when coming in contact with each other? Try a different deodorant to see if that helps.
LDS may be correct that it is a simple fungal infection.
Silly question but do you suffer from dry skin in winter? It could be that you skin is dry causing a slight reaction. I would dry not using it for a bit and just use baby powder for a day or two on the weekend and see if it helps.